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Tropical time series, iterated-sums signatures and quasisymmetric functions

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 نشر من قبل Joscha Diehl
 تاريخ النشر 2020
  مجال البحث الهندسة المعلوماتية
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Driven by the need for principled extraction of features from time series, we introduce the iterated-sums signature over any commutative semiring. The case of the tropical semiring is a central, and our motivating, example, as it leads to features of (real-valued) time series that are not easily available using existing signature-type objects.



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